How to Grow Cucumbers From Seed

This is the easiest way

cucumber seedlings in a pot

The Spruce / Margot Cavin

There’s nothing quite as satisfying as the crunch of a fresh, cool cucumber on a hot summer day. Cucumbers are like the air conditioning of the plant world—you just can’t get through a hot southern summer without them. They are good for snacks, salads, and even skincare. Cucumbers can even make water better. And when the summer is coming to a close, you can pickle the rest of the harvest to enjoy all year long.

With cucumbers used up daily, it’s important to make sure they are all organic. The dirty dozen list features cucumbers again this year, and you don’t want to consume that much of a vegetable that can be contaminated with pesticides and residue.

Although cucumbers can run into issues with pests, they are pretty simple to turn into a huge crop. Here’s how to start cucumbers from seed for your garden this year.

How to Grow Cucumbers

Since they need warmer temperatures, cucumber seeds can be started outdoors when the soil has warmed to around 70 degrees. Watch for your melons and other pumpkin-family plants to have already sprouted, then sow cucumber seeds. If you need to lengthen your growing season, plant indoors a few weeks before this time so that you are transplanting growing sprouts. Just be very sure that the soil is warm and there is no chance of frost!

Cucumbers are traditionally planted in rows or on mounds, allowed to sprawl along the ground. As a member of the pumpkin and gourd family, cucumber plants can take up quite a bit of space. For more intensive results, or just for some added aesthetic appeal, you can train cucumbers to climb a fence or trellis. You can set a trellis in a larger container and turn sprawling cucumbers into a contained potted plant!

Plant seeds a half-inch into the soil and 6 to 10 inches apart, then thin to one and a half to two feet apart—trellised cucumbers need to be two feet apart. Water frequently, increasing even more as the fruit begins to form. Cucumbers are 90 percent water, so it’s very important to keep them watered well.

Harvest cucumbers when they are smaller. Letting them grow too big will affect flavor and quality. Plus, if just one cucumber grows long enough that the seeds become mature, the entire plant will stop producing cucumbers. Pick them frequently to keep the plant growing and harvest coming!

planting cucumber seeds

The Spruce / K. Dave

cucumber seedlings

The Spruce / K. Dave

cucumber seedlings

The Spruce / K. Dave

cucumber preparing to fruit
​The Spruce / Margot Cavin
cucumbers ready for harvest

The Spruce / K. Dave

Cucumber Pests and Disease

Like all gourds, cucumbers are prone to pests and disease if not tended carefully. The first line of defense is choosing a good variety. Asian cucumbers, for example, are more disease resistant than larger varieties. Straight Eight is resistant to the mosaic virus, a common cucumber malady. Tasty Jade is another Asian variety that grows very well on a trellis. Planting seeds too early or too close together can invite mosaic virus and stem rot, as well.

The cucumber beetle is the most likely pest to target your crop. Parasitic nematodes can help curb them, as well as simply picking them off. Tansies have been shown to deter cucumber beetles, too.

Crop Rotation for Success

One major key to avoiding pests and disease lies in crop rotation. If you have heavy feeding, pest-attracting gourds in the same place season after season, they will be more and more prone to problems. Try to plant cucumbers after spinach or legumes, and follow them with a nitrogen-fixing ground cover like clover during the winter.

Most organic pest control methods revolve around prevention, so give your cucumbers a good environment and they will likely thrive.